Hard Lurch - 2009 Tacoma

I have a 2009 4 door Tacoma with a camper shell on it and recently I have noticed a very hard lurch or jerk when stopping quickly. The first time it happened, I thought I got rear ended because it barked the tires. I believe I have it narrowed down to two things, but I would like to get some input first. Many posts claim that it may be caused by axle wrap, however the truck has a headstrong 3 leaf aal pack which I believe should be more than sufficient to prevent the bed from sagging from braking? The second is that it may be a shift solenoid, but it has never tripped a code for it and I can't find a way to diagnose it. Anyone experience this or have any input?